Send your marbles through the “GraviTrax Tunnels” for surprising race results!

Add some stealth and an element of surprise with the “GraviTrax Tunnels Expansion” set! Packed with 18 components, use straight, curved and vertical tunnels to hide your marbles as they fly through your tracks, or help fast-moving marbles navigate sharp turns. Test the Bernoulli track to see how much speed you can generate, or drop the marble to a level below with the cool o-tracks. Combine with any “GraviTrax Starter-Set” to experience the power of gravity and educational fun today!

What makes a great toy? GraviTrax checks all the boxes! It's a creative, modular, expandable track system that challenges children to use their imagination to build their own marble runs! Electronic-free, GraviTrax construction sets use STEM-friendly concepts while building critical thinking and problem-solving skills. Completely open-ended, every GraviTrax set has a boredom-busting variety of play options for hours of fascinating fun. Once the basics are mastered, simply add expansion sets and accessories to propel those metal marbles around the tricked-out track of your dreams!

Comes complete with 4 curved Tunnels, 2 straight Tunnels, 2 Y-junction Tunnels, 2 card bases, 1 vertical U-turn, 2 drop o-tracks, 2 bowed Bernoulli tracks and instructions.

Lasting durability for girls and boys ages 8 and up, it's the learning toy children (and savvy adults) return to over and over again!